1. Field of the Invention
The present invention relates to a stator for a rotary electric machine, including a stator core and a stator winding provided to the stator core, which is configured by electrically connecting a plurality of coil portions formed by winding conductors around teeth to terminal members through connecting wires of the coil portions, and a method for manufacturing the stator.
2. Description of the Related Art
A rotary electric machine used as a driving source of electric automobiles and hybrid automobiles generally includes a ring-shaped stator core which has a plurality of teeth, each projecting in an inner-diameter direction, provided at constant intervals in a circumferential direction. A coil portion formed by winding a conductor is mounted to each of the teeth of the stator core (for example, see Japanese Patent No. 4340740).
For the stator as described above, the coil portions are formed into a unit in advance in accordance with the shapes of the respective teeth so as to facilitate assembly. Then, each of the coil portions is inserted over a corresponding one of the teeth to manufacture the stator.
In this case, after the coil portions are respectively inserted over the teeth, predetermined ones of the coil portions are required to be electrically connected to each other.
The coil portions are connected to each other by connecting a connecting wire of a terminal member provided on the outer diameter side of the stator core and a connecting wire of each of the coil portions on the inner diameter side. Of the two connecting wires, the connecting wire drawn from an innermost diameter portion of a coil main-body portion of the coil portion has a concave bent portion which is recessed in a direction closer to an end surface of the stator core.
The stator for the rotary electric machine described in Japanese Patent No. 4340740 includes the connecting wire having the concave bent portion recessed in the direction closer to the end surface of the stator core. On the inner diameter side of the stator core, however, the connecting wire bulges outward in an axial direction. Therefore, there is a problem in that a space for the bulge is required to be ensured on the end surface of the stator core.
Moreover, a portion of each of the coil portions on the outer diameter side of the stator core is located at a high position as compared with a portion of each of the coil portions on the inner diameter side of the stator core. In addition, the concave bent portion of the connecting wire is formed on the outer diameter side of the stator core.
Therefore, in order to ensure an insulation property between the connecting wires and the coil portions, an insulating distance is required to be ensured on the outer diameter side of the stator core, on which a potential is high. On the inner diameter side of the stator core, on which the connecting wire necessarily bulges outward in the axial direction, the insulating distance becomes longer than needed. Therefore, there is a problem in that the space for providing the connecting wire is required to be increased on the end surface of the stator core.